Unqualified Soure Material - Lot Size (ASME Sect. III)

[MattBat]

Hi everybody,

I think I have answered my own question, but I want your opinions to doubleckeck.

Dilemma:
If we buy unqualified source material and test each piece of steel (product analysis only) and the material is marked with the same steel heat number by the mill, are we allowed to then bundle these pieces together and make one "lot" out of them? The advantage is that it would decrease the number of destructive testing lots to 1 for the finished material and that we could recycle the steel heat number for the finished material.

My interpretation:
I would answer the question with a no due to the fact that the "lot" would be untraceable to the specific tests we have performed on each piece of the staring material. Product analyses with similar results are by no means a guarantee that the material comes from the same steel heat. In addition the recycling of a steel heat number from a mill is not necessarily a unique identification to the tests performed on the final material.

Thanks for checking!

Cheers,
Matthias

 

[Duwe6]

Gotta disagree. One of the definitions of "Lot" is all from the same Heat Number of metal. As long as all subsequent processing of the metal is identical from piece to piece, they are considered one Lot.

Look at the testing required in the basic ASME material spec's like SA-106, SA-516 Gr 70, etc. The only thing you seem to be missing is assiging a Lot # and *marking it on each part*. Unmarked parts are paperweights, no traceability to the Lot testing. But there is no reason that you cannot apply your own marking to your Lot. Hand-marking is acceptable, just get out your "paint-stick" and apply your own Lot # to each tested LOt.

 

[qcrobert]

I concur with Duwe6 in that we have followed same procedure with blessing of our AI.

 

[MattBat]

Thanks for the replies!

It seems I have to take a look at the Code again.

Cheers,
Matthias